Carbon content basic data

The major rivers investigated are given in Fig. 1. In this article we report on the nature and content of organic carbon carried by the major world rivers based on data collected during the first two years of the study. Some data on studies on the european estuaries are also presented. For sampling locations and basic data see the chapters on individual rivers in Degens (1982), Degens et al. (1983, 1985). 

The same plasma polymer deposited in a closed-system reactor has a graded elemental composition with a carbon-rich top surface, and the oligomer content is much lower [10], both of which increase the level of adhesion. The adhesion of the same water-borne primer is excellent and survives 8 h immersion in boiling water. When this surface is treated with O2 plasma, the adhesion does not survive 1 h of boiling, while the dry tape test still remains at the level of 5. The water-sensitivity of adhesion depends on the chemical nature of the top surface as depicted by XPS data shown in Figure 28.12. Water-insensitive tenacious adhesion, coupled with good transport barrier characteristics, provides excellent corrosion protection, as supported by experimental data [1-4], and constitutes the basic principle for the barrier-adhesion approach. 

The paraffinic carbon composition is similar for both groups of acid/ether extracted organics as is the presence of mono- and diaromatic compounds. No significant pH effects are observed, although the basic HC1 extract has a lower aromatic content than either the pH 1 or 6.5 fraction. The NMR data for the first bitumen fraction indicate that it is also predominantly paraffinic, in agreement with the earlier results of Spiro. (2 )... 

Weak basicity is exhibited by tt electrons in C = C double bonds and aromatic systems. Evidence for the protonation of basal plane sites on carbons was presented by Leon y Leon et al. [56]. In Fig. 13.5 of Ref [61] a ratio of 2.55 of adsorbed HCl (in mol) per mol of chemisorbed O atoms was given for a carbon black with a low oxygen content. The oxygen content before immersion was taken as a basis. This is much higher than the ratio of 1 expected for pyrone-type structures. However, from the data in Table 2 of this reference, a HCl/O ratio of 1.28 can be calculated, which is much closer to 1. 

The data bank on basic physical and chemical properties of individual substances stores the following data the name of the substance, molecular mass, the structural formula of the molecule and the number of carbon atoms, melting and boiling temperatures at atmospheric pressure, critical parameters, acentric factor and polarity, parameters of the Lennard-Jones and Stockmayer potentials, the coefficients of an equation for calculation of isobaric heat capacity in the ideal-gas state and some other properties. The content of the bank is enlarged continuously by input of information on new substances. 

Table 6.28 provides an overview on basic fuel data, gasifier features, performance figures, and gas qualities. The performance values for the Schwarze Pumpe waste-coal mix gasification are based on averaged data for the waste menu, which is not very well reconciled with the product gas. The main reason is that 80% of the gas originates from pyrolysis, because of extremely high volatiles content of the fuel [185]. Hence, the calculated values for cold gas efficiency, syngas yield, and carbon conversion are not very reliable. 

As described above, it is obvious from the free energy data that oxides and oxysulfides would be formed first when rare earths are added to molten iron, and sulfur removal is effective only when the oxygen content and its activity are low. Use of a heavy basic slag and 0.2% mischmetal (residual Ce in steel 0.002-0.015%) reduced the sulfur content in one case from 0.012% to <0.001% in plain carbon steels and C 0.003% in 12-13% Cr stainless steels (Grevillius et al. 1971). A 0.5% mischmetal addition resulted in 94% sulfur removal in another case (Bernard 1967). Similar results have been obtained by Dahl et al. (1973). 

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